I used Sharkbite brand fittings this time. I've never used them before. They're more expensive, but they are really easy to put together. If I had used the Rehau fittings, I'd have to rent the installation tools for $25 a day. In the end, the Sharkbite fittings were cheaper.
After I got all the plumbing in the wall, I put in insulation (to minimize noise and to insulate the water heater room).
Here are photos of the washer/dryer closet.
And here is a photo of the water heater closet.
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You may have noticed that I left some holes in the drywall where the plumbing connections are. I want to verify that there are no leaks before I seal up the wall. I'll patch the holes later after I've hooked up the plumbing.
And here is a photo of the other side of the closet wall (the den wall) before it was filled with insulation and closed up.